The body was wrapped up in clothing and plastic bags, said Greater Manchester Police (GMP).

Officers also recovered a note which requested that the baby receive an Islamic burial. The age, sex and ethnicity of the baby is not yet known and it is unclear whether the baby was born alive or stillborn.

Chief Inspector Carol Martin said: "Obviously this is an extremely upsetting incident and our investigation at the moment is twofold: finding out how and when the baby died, and locating the parents. I cannot begin to imagine what either parent may be going through and we are very worried about their physical and emotional state.

"It is likely the mother in particular will require some form of medical attention and I want to appeal directly to both parents or anyone who knows them to contact police or visit your GP or local hospital. It is vitally important that I stress support networks are in place and are waiting and on hand to help the parents."

Ms Martin added: "While we cannot speculate on the ethnicity of either parent, there was a note left requesting the baby receive an Islamic burial and we have already reached out to the Muslim community through their Friday prayers through our partnership connections at the Bolton Council of Mosques.

"The answer undoubtedly lies somewhere in the community and I want to ask the Bolton community as a whole whether they know of anyone who may have tried to conceal a birth or who recently has been pregnant but now is without a baby or appears withdrawn, upset or in physical discomfort.

"I also want to appeal to residents in the Lostock area who perhaps use Ox Hey Lane for running, cycling or walking on a frequent or daily basis: have you noticed a pile of what appeared to be clothing and plastic bags in the shrubbery off the tarmaced area recently? If so, please call us."

Anyone with information is asked to call police on 0161 856 5599, or Crimestoppers anonymously on 0800 555 111.